Vehicles with endless tracks are in contact with a larger surface area of the ground than a wheeled vehicle. The larger surface area results in a much lower force per unit area on the ground being traversed than a conventional wheeled vehicle of the same weight. This makes vehicles with endless tracks highly mobile and able to travel over most types of terrain. Vehicles with endless tracks have applications in military use, heavy commercial use, and others where the vehicle may travel over varying terrain.
The principal disadvantage is that a vehicle with an endless track is a more complex mechanism than a vehicle without an endless track. Each track link assembly must pivot relative to adjacent track link assemblies to accommodate changes in the ground surface and to follow a track progression around suspension components. The load of the vehicle, acceleration and deceleration of the vehicle, the wearing of the ground, the wearing of contacting components such as road wheels and a drive sprocket, as well as the relative pivoting of adjacent track link assemblies all cause degradation in the useful life of each track link assembly. Due to this degradation in useful life, track link assemblies must be maintained and replaced from time to time.
Degradation in useful life of a track link assembly can place limitations on a vehicle's long-range mobility. The higher need for maintenance lowers the vehicle's readiness and can come about at inopportune times, especially if the vehicle is being used in a war zone. Required replacement and maintenance of track link assemblies raise the costs of operating tracked vehicles and decreases the tracked vehicle's readiness.
Among the references considered before filing this application are: U.S. Pat. No. 5,853,233 to Turner, U.S. Pat. No. 5,069,510 to Cory, U.S. Pat. No. 4,813,750 to Erlenmaier et al., and U.S. Pat. No. 4,668,025 to Macdonald.